I agree with you on all that... JF's story makes no sense, he contradicts himself, it appears he doesn't have the self-control to conceal his "duper's delight" smirk, and (apparently) he thinks the police don't suspect him.
Where I disagree is this: four months is a long time in a disappearence/ murder. In practical terms, the killer has a four month head start. There's a reason they called that show "The First 48" - if they don't get a lead in the first 48 hours, the probability of solving the homicide drops substantially.
People's memories get hazy, security camera footage is deleted, a body decomposes, DNA breaks down, dumpsters are emptied, landfills fill up with trash, the killer has time to clean up loose ends, and the forensics become stale.
Modern judges and juries have come to expect forensic evidence. We know JF has made an 'electronic alibi' - probably a couple of fake texts using Elora's phone. Unless the RCMP have (or find) the sort of evidence to contradict his story (a body, blood, cameras, trace evidence), I think there won't be enough probable cause for an indictment, let alone enough evidence to secure a conviction.
About 1 in 6 people reading this thread think no homicide has taken place. The RCMP will need something tangible to contradict JF's story that would meet the legal standard of proof.
Most importantly: Even in Canada, 40% of homicides go unsolved.